(1) Field of the Invention
The present invention relates to a fault monitoring apparatus for a mobile communication system, and more particularly to a fault monitoring apparatus for a mobile communication system based on the standards of the Research & Development Center for Radio System (RCR).
(2) Description of the Related Art
Generally, mobile communication systems are made up of a single mobile switching center (MSC), hundreds of base stations (BS) connected to the mobile switching center via wired transmission paths, and mobile stations (MS) positioned in radio service zones of the base stations and connected to the base stations via radio transmission paths. A base station control equipment (BCE) is connected to the mobile switching center.
Heretofore, it has been customary for the maintenance personnel to monitor the base stations through the base station control equipment to detect faults that may occur in the base stations.
Specifically, the maintenance personnel refer to call processing alarms which the base station control equipment collects from the base stations through the mobile switching center at all times, and recognize the occurrence of a fault when the content of an indicated reason of any one of the call processing alarms represents either one of time-out of a response to a channel allocation request, time-out of a response to a reception level measurement request, and time-out of a response to a radio channel designation request. The maintenance personnel designates the transceiver (TRX) of a base station where a fault is possibly occurring, and conducts a radio wave level measurement test on the controller of the base station.
In the radio wave level measurement test, radio waves in respective channels are transmitted and received between the designated transceiver of the base station and a test transceiver (TTR) in the base station via the radio transmission path. The designated transceiver and the test transceiver measure received levels in frequency bands of the respective channels and adjacent frequency bands, and send the measured values to the maintenance personnel. The maintenance personnel then specify a faulty channel and a faulty device based on the measured values.
According to the conventional base station monitoring practice, the maintenance personnel refer to call processing alarms, detect the occurrence of a fault in a base station, and conduct a radio wave level measurement test.
However, the manual fault detection process is disadvantageous in that the maintenance personnel may not necessarily start an immediate fault detection procedure, and it may take too a long period of time before a fault is detected if the maintenance personnel conduct a fault detection procedure only several times a day.
As described above, the occurrence of a fault in a base station has heretofore been detected on the basis of call processing alarms. Since the detection process based on call processing alarms tends to detect cases other than true faults in base stations, however, a radio wave level measurement test may possibly be conducted on cases which do not require such a test.